Superior Fast-Charging Lithium-Ion Batteries Enabled by the High-Speed Solid-State Lithium Transport of an Intermetallic Cu6 Sn5 Network.

Superior fast charging is a desirable capability of lithium-ion batteries, which can make electric vehicles a strong competition to traditional fuel vehicles. However, the slow transport of solvated lithium ions in liquid electrolytes is a limiting factor. Here, a Lix Cu6 Sn5 intermetallic network is reported to address this issue. Based on electrochemical analysis and X-ray photoelectron spectroscopy mapping, it is demonstrated that the reported intermetallic network can form a high-speed solid-state lithium transport matrix throughout the electrode, which largely reduces the lithium-ion-concentration polarization effect in the graphite anode. Employing this design, superior fast-charging graphite/lithium cobalt oxide full cells are fabricated and tested under strict electrode conditions. At the charging rate of 6 C, the fabricated full cells show a capacity of 145 mAh g-1 with an extraordinary capacity retention of 96.6%. In addition, the full cell also exhibits good electrochemical stability at a high charging rate of 2 C over 100 cycles (96.0% of capacity retention) in comparison to traditional graphite-anode-based cells (86.1% of capacity retention). This work presents a new strategy for fast-charging lithium-ion batteries on the basis of high-speed solid-state lithium transport in intermetallic alloy hosts.

Thermal tuning of mode crossing and the perfect soliton crystal in a Si3N4 microresonator.

Dissipative Kerr solitons in high quality microresonators have attracted much attention in the past few years. They provide ideal platforms for a number of applications. Here, we fabricate the Si3N4 microring resonator with anomalous dispersion for the generation of single soliton and soliton crystal. Based on the strong thermal effect in the high-Q microresonator, the location and strength of the avoided mode crossing in the device can be changed by the intracavity power. Because the existence of the avoided mode crossing can induce the perfect soliton crystal with specific soliton number, we could choose the appropriate pumped resonance mode and appropriate pump power to obtain the perfect soliton crystals on demand.

Three-dimensionally ordered Macroporous perovskite sodium tantalum for robust hydrogen and hydrogen peroxide production.

Constructing photocatalytic materials into three-dimensionally ordered macroporous (3DOM) is considered an effective strategy for improving mass transfer behaviors and shortening the electron migration path. However, this strategy is challenging for ternary semiconductors because they cannot be directly synthesized by traditional thermal decomposition methods. Ternary systems need to face the structural instability caused by the construction of macroporous morphology, which limits the application of the ordered macroporous structure. In this work, we designed a novel and efficient two-step crystal nucleation strategy for constructing a highly stable ternary ordered macroporous structure. Here, 3DOM NaTaO3 was reported as a promising candidate. Compared with nonporous NaTaO3, which has no catalytic activity in pure water, 807.9 and 280.1 µmol g-1h-1 of H2 and H2O2 production rates were first achieved on the 3DOM NaTaO3. Furthermore, the rate of photocatalytic H2 evolution over the 3DOM NaTaO3 improved sharply to 3.9 mmol g-1h-1 in methanol aqueous solution, which was 139 times that of nonporous NaTaO3. The construction of 3DOM NaTaO3 enables the participation of the bulk interior in photochemical reaction and provides more options for later decoration. This work opens a new door for constructing more 3DOM ternary semiconductors for catalytic reactions.

3D-Zipped Interface: In Situ Covalent-Locking for High Performance of Anion Exchange Membrane Fuel Cells.

Polymer electrolyte membrane fuel cells can generate high power using a potentially green fuel (H2 ) and zero emissions of greenhouse gas (CO2 ). However, significant mass transport resistances in the interface region of the membrane electrode assemblies (MEAs), between the membrane and the catalyst layers remains a barrier to achieving MEAs with high power densities and long-term stabilities. Here, a 3D-interfacial zipping concept is presented to overcome this challenge. Vinylbenzyl-terminated bi-cationic quaternary-ammonium-based polyelectrolyte is employed as both the anionomer in the anion-exchange membrane (AEM) and catalyst layers. A quaternary-ammonium-containing covalently locked interface is formed by thermally induced inter-crosslinking of the terminal vinyl groups. Ex situ evaluation of interfacial bonding strength and in situ durability tests demonstrate that this 3D-zipped interface strategy prevents interfacial delamination without any sacrifice of fuel cell performance. A H2 /O2 AEMFC test demonstration shows promisingly high power densities (1.5 W cm-2 at 70 °C with 100% RH and 0.2 MPa backpressure gas feeds), which can retain performances for at least 120 h at a usefully high current density of 0.6 A cm-2 .

Boosting photoelectrochemical efficiency by near-infrared-active lattice-matched morphological heterojunctions.

Photoelectrochemical catalysis is an attractive way to provide direct hydrogen production from solar energy. However, solar conversion efficiencies are hindered by the fact that light harvesting has so far been of limited efficiency in the near-infrared region as compared to that in the visible and ultraviolet regions. Here we introduce near-infrared-active photoanodes that feature lattice-matched morphological hetero-nanostructures, a strategy that improves energy conversion efficiency by increasing light-harvesting spectral range and charge separation efficiency simultaneously. Specifically, we demonstrate a near-infrared-active morphological heterojunction comprised of BiSeTe ternary alloy nanotubes and ultrathin nanosheets. The heterojunction's hierarchical nanostructure separates charges at the lattice-matched interface of the two morphological components, preventing further carrier recombination. As a result, the photoanodes achieve an incident photon-to-current conversion efficiency of 36% at 800 nm in an electrolyte solution containing hole scavengers without a co-catalyst.

Study on correlation between coagulation indexes and disease progression in patients with cirrhosis.

OBJECTIVE: To inquire into the significance of coagulation indexes in the progression of cirrhosis. METHODS: A total of 108 patients with cirrhosis treated in our hospital were collected as the research group (RG), and 105 healthy people who underwent concurrent physical examination were selected as the control group (CG). The coagulation indexes of all the participants were tested to determine their significance in cirrhosis progression. RESULTS: Compared with the CG, prothrombin time (PT), activated partial thrombin time (APTT) and thrombin time (TT) in the RG were statistically prolonged, while fibrinogen (FIB) was notably decreased (P<0.05). With the increase of Child-Pugh score, PT, APTT and TT prolonged and FIB reduced gradually (P<0.05). The coagulation indexes of patients were correlated with Child-Pugh score (P<0.05). Patients in the RG showed markedly higher alanine aminotransferase (ALT), total bilirubin (TBil), total bile acid (TBA), mean platelet volume (MPV), platelet distribution width (PDW) and platelet-large cell ratio (P-LCR), with notably lower albumin (ALB), prealbumin (PA), platelet count (PLT) and coagulation factors compared with the CG. As the Child-Pugh score increased, the ALT, TBil, TBA, MPV, PDW and P-LCR gradually elevated in the RG (P<0.05), whilst coagulation factors, ALB, PLT and PA all gradually decreased (P<0.05). The value of area under the curve (AUC) of each coagulation index for early diagnosis of cirrhosis was >0.80, and the sensitivity was >80% (P<0.05). CONCLUSION: Coagulation indexes, coagulation factors, platelet parameters and liver function all effectively reflect the level of liver injury; especially which, coagulation indexes are related to the severity of liver injury, and can provide evidence for the early diagnosis of cirrhosis patients, with clinical significance.

Multi-scale design of the chela of the hermit crab Coenobita brevimanus.

The chela of the hermit crab protects its body against the attack from predators. Yet, a deep understanding of this mechanical defense is still lacking. Here, we investigate the chela of hermit crab, Coenobita brevimanus, and establish the relationships between the microstructures, chemical compositions and mechanical properties to gain insights into its biomechanical functions. We find that the chela is a multi-layered shell composed of five different layers with distinct features of the microstructures and chemical compositions, conferring different mechanical properties. Especially, an increase of the calcium carbonate content towards the layer furthest from the exterior, unlike the chemical gradients of many crustacean exoskeletons, provides a strong resistance to deformation. Nanoindentation measurements reveal that the overall gradient of the elastic modulus and hardness in the cross-section displays a sandwich profile, i.e., a soft core clamped by two stiff surface layers. Further mechanics modeling demonstrates that the high curvature and stiff innermost sublayer enhance the structural rigidity of the chela. In conjunction with the experimental observations, dynamic finite element analysis maps the time-spatial distribution of principal stress and indicates that fiber bridging might be the major mechanism against crack propagation at microscale. The lessons gained from the study of this multiphase biological composite could provide important insights into the design and fabrication of bioinspired materials for structural applications. STATEMENT OF SIGNIFICANCE: Multiple hierarchical structures have been discovered in a variety of exoskeletons. They are naturally designed to maintain the structural integrity and act as a protective layer for the animals. However, each kind of the hierarchical structures has its unique topology, chemical gradients as well as mechanical properties. We find that the chela is multi-layered shell composed of five different layers with distinct features of the microstructures and chemical compositions, conferring different mechanical properties. Especially, a large amount of helicoidal organic fibrils form highly organized 3D woven matrix in the innermost layer, providing a strong mechanical resistance to avoid catastrophic failure. The overall gradient of the elastic modulus and hardness in the cross-section display a sandwich profile, effectively minimizing the stress concentration and deformation. The lessons gained from the multiscale design strategy of the chela provide important insights into the design and fabrication of bioinspired materials.

Optimized Hierarchical Structure and Chemical Gradients Promote the Biomechanical Functions of the Spike of Mantis Shrimps.

The tail spike of the mantis shrimp is the appendage for counteracting the enemy from behind. Here, we investigate the correlations between the chemical compositions, the microstructures, and the mechanical properties of the spike. We find that the spike is a hollow beam with a varying cross section along the length. The cross section comprises four different layers with distinct features of microstructures and chemical compositions. The local mechanical properties of these layers correlate well with the microstructures and chemical compositions, a combination of which effectively restricts the crack propagation while maximizing the release of strain energy during deformation. Finite element analysis and mechanics modeling demonstrate that the optimized structure of the spike confines the mechanical damage in the region near the tip and prevents catastrophic breakage at the base. Furthermore, we use a 3D printing technique to fabricate multiple hollow cylindrical samples consisting of biomimetic microstructures of the spike and confirm that the combination of the Bouligand structure with radially oriented parallel sheets greatly improves the toughness and strength during compression tests. The multiscale design strategy of the spike revealed here is expected to be of great interest for the development of novel bioinspired materials.

The availability, price and affordability of antidiabetic drugs in Hubei province, China.

Based on the high prevalence and undiagnosed rate of diabetes mellitus in China in recent years, the aim of this work was to evaluate the availability, price and affordability of pharmacotherapy for diabetes in public hospitals in Hubei province, China. In 2016, a cross-sectional survey was conducted using World Health Organization/Health Action International (WHO/HAI) methodology. Information on the availability and prices of 20 antidiabetic drugs was collected from 34 public hospitals representing three levels of care. Of the 20 antidiabetic drugs, 70.6% were below 50% availability. Total availability of the 20 drugs was higher in secondary and tertiary hospitals than in primary hospitals. All three hospital levels had higher availability of essential than non-essential antidiabetic medicines. The median markup ratios of originator brands (OBs) and lowest-price generics (LPGs) were 15.6% and 2.1%, respectively. The median potential saving ratio of using generics was 31.3%. Overall, the median affordability of 31 antidiabetic drugs ranged from 1.2 to 8.5 days of disposable income for residents with three income levels. After insurance reimbursement, the increase in the proportion of affordable drugs in urban and rural areas averaged 35.5% and 12.9%, respectively. The proportion of drugs with low availability and low affordability dropped from 54.8% to 38.7%. However, 41.7% of urban diabetic patients and 74.0% of rural diabetic patients remained unable to afford the drugs surveyed. Higher income and generic substitution are factors facilitating affordability. In Hubei province, the overall availability of 20 antidiabetic drugs was low, especially in primary hospitals. The affordability of most drugs surveyed was also low. Current health insurance can greatly improve affordability for urban residents with middle or high income. Policy changes should focus on the supply, pricing and clinical use of antidiabetic drugs and special health insurance plan for low income population with diabetes.

QTc prolongation and torsades de pointes due to a coadministration of fluoxetine and amiodarone in a patient with implantable cardioverter-defibrillator: Case report and review of the literature.

RATIONALE: Drug-induced prolongation of the corrected QT interval (QTc) may lead to serious and potentially life-threatening ventricular tachyarrhythmia, such as torsades de pointes (Tdp), which is worthy of clinical attention. Here, we report 1 case of Tdp after a coadministration of fluoxetine and amiodarone. PATIENT CONCERNS: A 62-year-old Chinese male who placed with the implanted cardioverter-defibrillator (ICD) appeared the QTc prolongation and Tdp after the concurrent administration of fluoxetine and amiodarone. DIAGNOSES: Torsades de pointes (Tdp). INTERVENTIONS: The patient was treated with magnesium and potassium immediately. Her ICD-brady pacing mode was reprogrammed to 90 bpm. Meanwhile, both of fluoxetine and amiodarone were discontinued. OUTCOMES: The further episodes of Tdp were prevented. After a few days, the QTc gradually decreased without clinically significant arrhythmias. LESSONS: The present case demonstrates that a potential drug-drug interaction (DDI) may lead to a life-threatening drug adverse reaction (ADR) especially in special subjects. Therefore, clinicians should closely monitor the electrocardiogram (ECG) when QTc-prolonging agents are given to patients with cardiac abnormalities, and avoid combining 2 QTc-prolonging drugs.

An integrated microsystem with dielectrophoresis enrichment and impedance detection for detection of Escherichia coli.

An integrated microsystem device with matched interdigitated microelectrode chip was fabricated for enrichment and detection of Escherichia coli O157:H7. The microsystem has integrated with positive dielectrophoresis (pDEP) enrichment and in situ impedance detection, whose total volume is only 3.0 × 10-3 m3, and could provide impedance testing voltages of 0 ~ 10 V, detection frequencies of 1 KHz ~ 1 MHz, DEP excitation signals with amplitude of 0 ~ 10 Vpp and frequencies of 1KHz ~ 1 MHz, which fully meets the demands of pDEP enrichment and impedance detection for bacteria. The microfluidic chip with interdigitated microelectrodes was manufactured by microfabrication methods. The interdigital microelectrode array has sufficient contact area with a bacterial suspension to improve enrichment efficiency and detection sensitivity. Bacteria in the interdigital microelectrode area of the microfluidic chip were firstly captured and enriched by pDEP. Then, in situ impedance detection of the enriched bacteria was realized by switching test conditions. Using the self-assembly microsystem, a novel quantitative detection method was established and demonstrated to detect Escherichia coli O157:H7. Experimental results showed that the detection limits of Escherichia coli O157:H7 was 5 × 104 cfu mL-1, and testing time was only 6 min under the optimized detection voltage of 100 mV and frequency of 500 KHz. The method was successfully used to detect Escherichia coli O157:H7 in synthetic chicken synthetic samples.

Ecotone shift and major droughts during the mid-late Holocene in the central Tibetan Plateau.

A well-dated pollen record from a large lake located on the meadow-steppe ecotone provides a history of ecotone shift in response to monsoonal climate changes over the last 6000 years in the central Tibetan Plateau. The pollen record indicates that the ecotone shifted eastward during 6000-4900, 4400-3900, and 2800-1600 cal. yr BP when steppes occupied this region, whereas it shifted westward during the other intervals when the steppes were replaced by meadows. The quantitative reconstruction of paleoclimate derived from the pollen record shows that monsoon precipitation fluctuated around the present level over the last 6000 years in the central Tibetan Plateau. Three major drought episodes of 5600-4900, 4400-3900, and 2800-2400 cal. yr BP are detected by pollen signals and lake sediments. Comparison of our record with other climatic proxy data from the Tibetan Plateau and other monsoonal regions shows that these episodes are three major centennial-scale monsoon weakening events.